#include "../include/lib/crypto.hpp"

namespace remmel
{
    Str MD5(Str source)
    {
        uint32_t MD5_A = 0x67452301,
                 MD5_B = 0xefcdab89,
                 MD5_C = 0x98badcfe,
                 MD5_D = 0x10325476;
        uint32_t len = 0;
        Vec<uint32_t> rec = md5_padding(source, len);
        for (uint32_t i = 0; i < len / 16; i++)
        {
            uint32_t num[16];
            for (int j = 0; j < 16; j++)
                num[j] = rec[i * 16 + j];
            md5_iterateFunc(num, MD5_A, MD5_B, MD5_C, MD5_D);
        }
        return md5_format(MD5_A) + md5_format(MD5_B) + md5_format(MD5_C) + md5_format(MD5_D);
    }

    void md5_iterateFunc(uint32_t *X, uint32_t &tempA, uint32_t &tempB, uint32_t &tempC, uint32_t &tempD, int size)
    {
        uint32_t a = tempA,
                 b = tempB,
                 c = tempC,
                 d = tempD,
                 rec = 0,
                 g, k;
        for (int i = 0; i < 64; i++)
        {
            if (i < 16)
            {
                g = MD5_F(b, c, d);
                k = i;
            }
            else if (i < 32)
            {
                g = MD5_G(b, c, d);
                k = (1 + 5 * i) % 16;
            }
            else if (i < 48)
            {
                g = MD5_H(b, c, d);
                k = (5 + 3 * i) % 16;
            }
            else
            {
                g = MD5_I(b, c, d);
                k = (7 * i) % 16;
            }
            rec = d;
            d = c;
            c = b;
            b = b + MD5_SHIFT(a + g + X[k] + MD5_T[i], MD5_S[i]);
            a = rec;
        }
        tempA += a;
        tempB += b;
        tempC += c;
        tempD += d;
    }

    Vec<uint32_t> md5_padding(Str src, uint32_t &len)
    {
        uint32_t num = ((src.length() + 8) / 64) + 1;
        Vec<uint32_t> rec(num * 16);
        len = num * 16;
        for (uint32_t i = 0; i < src.length(); i++)
            rec[i >> 2] |= (int)(src[i]) << ((i % 4) * 8);
        rec[src.length() >> 2] |= (0x80 << ((src.length() % 4) * 8));
        rec[rec.size() - 2] = (src.length() << 3);
        return rec;
    }

    Str md5_format(uint32_t num)
    {
        Str res, tmp;
        for (int i = 0; i < 4; i++)
        {
            tmp = "";
            uint32_t b = (num >> (i * 8)) % (1 << 8) & 0xff;
            for (int j = 0; j < 2; j++, b /= 16)
                tmp = MD5_HEX[b % 16] + tmp;
            res += tmp;
        }
        return res;
    }

/*****************************************************************************/
/* Defines:                                                                  */
/*****************************************************************************/
// The number of columns comprising a state in AES. This is a constant in AES. Value=4
#define Nb 4

#if defined(AES256) && (AES256 == 1)
#define Nk 8
#define Nr 14
#elif defined(AES192) && (AES192 == 1)
#define Nk 6
#define Nr 12
#else
#define Nk 4  // The number of 32 bit words in a key.
#define Nr 10 // The number of rounds in AES Cipher.
#endif

// jcallan@github points out that declaring Multiply as a function
// reduces code size considerably with the Keil ARM compiler.
// See this link for more information: https://github.com/kokke/tiny-AES-C/pull/3
#ifndef MULTIPLY_AS_A_FUNCTION
#define MULTIPLY_AS_A_FUNCTION 0
#endif

    /*****************************************************************************/
    /* Private variables:                                                        */
    /*****************************************************************************/
    // state - array holding the intermediate results during decryption.
    typedef uint8_t state_t[4][4];

    // The lookup-tables are marked const so they can be placed in read-only storage instead of RAM
    // The numbers below can be computed dynamically trading ROM for RAM -
    // This can be useful in (embedded) bootloader applications, where ROM is often limited.
    static const uint8_t sbox[256] = {
        // 0     1    2      3     4    5     6     7      8    9     A      B    C     D     E     F
        0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
        0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
        0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
        0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
        0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
        0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
        0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
        0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
        0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
        0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
        0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
        0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
        0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
        0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
        0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
        0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16};

#if (defined(CBC) && CBC == 1) || (defined(ECB) && ECB == 1)
    static const uint8_t rsbox[256] = {
        0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb,
        0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb,
        0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
        0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25,
        0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92,
        0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
        0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06,
        0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b,
        0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
        0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e,
        0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b,
        0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
        0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f,
        0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef,
        0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
        0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d};
#endif

    // The round constant word array, Rcon[i], contains the values given by
    // x to the power (i-1) being powers of x (x is denoted as {02}) in the field GF(2^8)
    static const uint8_t Rcon[11] = {
        0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36};

/*
 * Jordan Goulder points out in PR #12 (https://github.com/kokke/tiny-AES-C/pull/12),
 * that you can remove most of the elements in the Rcon array, because they are unused.
 *
 * From Wikipedia's article on the Rijndael key schedule @ https://en.wikipedia.org/wiki/Rijndael_key_schedule#Rcon
 *
 * "Only the first some of these constants are actually used – up to rcon[10] for AES-128 (as 11 round keys are needed),
 *  up to rcon[8] for AES-192, up to rcon[7] for AES-256. rcon[0] is not used in AES algorithm."
 */

/*****************************************************************************/
/* Private functions:                                                        */
/*****************************************************************************/
/*
static uint8_t getSBoxValue(uint8_t num)
{
  return sbox[num];
}
*/
#define getSBoxValue(num) (sbox[(num)])

    // This function produces Nb(Nr+1) round keys. The round keys are used in each round to decrypt the states.
    static void KeyExpansion(uint8_t *RoundKey, const uint8_t *Key)
    {
        unsigned i, j, k;
        uint8_t tempa[4]; // Used for the column/row operations

        // The first round key is the key itself.
        for (i = 0; i < Nk; ++i)
        {
            RoundKey[(i * 4) + 0] = Key[(i * 4) + 0];
            RoundKey[(i * 4) + 1] = Key[(i * 4) + 1];
            RoundKey[(i * 4) + 2] = Key[(i * 4) + 2];
            RoundKey[(i * 4) + 3] = Key[(i * 4) + 3];
        }

        // All other round keys are found from the previous round keys.
        for (i = Nk; i < Nb * (Nr + 1); ++i)
        {
            {
                k = (i - 1) * 4;
                tempa[0] = RoundKey[k + 0];
                tempa[1] = RoundKey[k + 1];
                tempa[2] = RoundKey[k + 2];
                tempa[3] = RoundKey[k + 3];
            }

            if (i % Nk == 0)
            {
                // This function shifts the 4 bytes in a word to the left once.
                // [a0,a1,a2,a3] becomes [a1,a2,a3,a0]

                // Function RotWord()
                {
                    const uint8_t u8tmp = tempa[0];
                    tempa[0] = tempa[1];
                    tempa[1] = tempa[2];
                    tempa[2] = tempa[3];
                    tempa[3] = u8tmp;
                }

                // SubWord() is a function that takes a four-byte input word and
                // applies the S-box to each of the four bytes to produce an output word.

                // Function Subword()
                {
                    tempa[0] = getSBoxValue(tempa[0]);
                    tempa[1] = getSBoxValue(tempa[1]);
                    tempa[2] = getSBoxValue(tempa[2]);
                    tempa[3] = getSBoxValue(tempa[3]);
                }

                tempa[0] = tempa[0] ^ Rcon[i / Nk];
            }
#if defined(AES256) && (AES256 == 1)
            if (i % Nk == 4)
            {
                // Function Subword()
                {
                    tempa[0] = getSBoxValue(tempa[0]);
                    tempa[1] = getSBoxValue(tempa[1]);
                    tempa[2] = getSBoxValue(tempa[2]);
                    tempa[3] = getSBoxValue(tempa[3]);
                }
            }
#endif
            j = i * 4;
            k = (i - Nk) * 4;
            RoundKey[j + 0] = RoundKey[k + 0] ^ tempa[0];
            RoundKey[j + 1] = RoundKey[k + 1] ^ tempa[1];
            RoundKey[j + 2] = RoundKey[k + 2] ^ tempa[2];
            RoundKey[j + 3] = RoundKey[k + 3] ^ tempa[3];
        }
    }

    void AES_init_ctx(struct AES_ctx *ctx, const uint8_t *key)
    {
        KeyExpansion(ctx->RoundKey, key);
    }
#if (defined(CBC) && (CBC == 1)) || (defined(CTR) && (CTR == 1))
    void AES_init_ctx_iv(struct AES_ctx *ctx, const uint8_t *key, const uint8_t *iv)
    {
        KeyExpansion(ctx->RoundKey, key);
        memcpy(ctx->Iv, iv, AES_BLOCKLEN);
    }
    void AES_ctx_set_iv(struct AES_ctx *ctx, const uint8_t *iv)
    {
        memcpy(ctx->Iv, iv, AES_BLOCKLEN);
    }
#endif

    // This function adds the round key to state.
    // The round key is added to the state by an XOR function.
    static void AddRoundKey(uint8_t round, state_t *state, const uint8_t *RoundKey)
    {
        uint8_t i, j;
        for (i = 0; i < 4; ++i)
        {
            for (j = 0; j < 4; ++j)
            {
                (*state)[i][j] ^= RoundKey[(round * Nb * 4) + (i * Nb) + j];
            }
        }
    }

    // The SubBytes Function Substitutes the values in the
    // state matrix with values in an S-box.
    static void SubBytes(state_t *state)
    {
        uint8_t i, j;
        for (i = 0; i < 4; ++i)
        {
            for (j = 0; j < 4; ++j)
            {
                (*state)[j][i] = getSBoxValue((*state)[j][i]);
            }
        }
    }

    // The ShiftRows() function shifts the rows in the state to the left.
    // Each row is shifted with different offset.
    // Offset = Row number. So the first row is not shifted.
    static void ShiftRows(state_t *state)
    {
        uint8_t temp;

        // Rotate first row 1 columns to left
        temp = (*state)[0][1];
        (*state)[0][1] = (*state)[1][1];
        (*state)[1][1] = (*state)[2][1];
        (*state)[2][1] = (*state)[3][1];
        (*state)[3][1] = temp;

        // Rotate second row 2 columns to left
        temp = (*state)[0][2];
        (*state)[0][2] = (*state)[2][2];
        (*state)[2][2] = temp;

        temp = (*state)[1][2];
        (*state)[1][2] = (*state)[3][2];
        (*state)[3][2] = temp;

        // Rotate third row 3 columns to left
        temp = (*state)[0][3];
        (*state)[0][3] = (*state)[3][3];
        (*state)[3][3] = (*state)[2][3];
        (*state)[2][3] = (*state)[1][3];
        (*state)[1][3] = temp;
    }

    static uint8_t xtime(uint8_t x)
    {
        return ((x << 1) ^ (((x >> 7) & 1) * 0x1b));
    }

    // MixColumns function mixes the columns of the state matrix
    static void MixColumns(state_t *state)
    {
        uint8_t i;
        uint8_t Tmp, Tm, t;
        for (i = 0; i < 4; ++i)
        {
            t = (*state)[i][0];
            Tmp = (*state)[i][0] ^ (*state)[i][1] ^ (*state)[i][2] ^ (*state)[i][3];
            Tm = (*state)[i][0] ^ (*state)[i][1];
            Tm = xtime(Tm);
            (*state)[i][0] ^= Tm ^ Tmp;
            Tm = (*state)[i][1] ^ (*state)[i][2];
            Tm = xtime(Tm);
            (*state)[i][1] ^= Tm ^ Tmp;
            Tm = (*state)[i][2] ^ (*state)[i][3];
            Tm = xtime(Tm);
            (*state)[i][2] ^= Tm ^ Tmp;
            Tm = (*state)[i][3] ^ t;
            Tm = xtime(Tm);
            (*state)[i][3] ^= Tm ^ Tmp;
        }
    }

// Multiply is used to multiply numbers in the field GF(2^8)
// Note: The last call to xtime() is unneeded, but often ends up generating a smaller binary
//       The compiler seems to be able to vectorize the operation better this way.
//       See https://github.com/kokke/tiny-AES-c/pull/34
#if MULTIPLY_AS_A_FUNCTION
    static uint8_t Multiply(uint8_t x, uint8_t y)
    {
        return (((y & 1) * x) ^
                ((y >> 1 & 1) * xtime(x)) ^
                ((y >> 2 & 1) * xtime(xtime(x))) ^
                ((y >> 3 & 1) * xtime(xtime(xtime(x)))) ^
                ((y >> 4 & 1) * xtime(xtime(xtime(xtime(x)))))); /* this last call to xtime() can be omitted */
    }
#else
#define Multiply(x, y)                         \
    (((y & 1) * x) ^                           \
     ((y >> 1 & 1) * xtime(x)) ^               \
     ((y >> 2 & 1) * xtime(xtime(x))) ^        \
     ((y >> 3 & 1) * xtime(xtime(xtime(x)))) ^ \
     ((y >> 4 & 1) * xtime(xtime(xtime(xtime(x))))))

#endif

#if (defined(CBC) && CBC == 1) || (defined(ECB) && ECB == 1)
/*
static uint8_t getSBoxInvert(uint8_t num)
{
  return rsbox[num];
}
*/
#define getSBoxInvert(num) (rsbox[(num)])

    // MixColumns function mixes the columns of the state matrix.
    // The method used to multiply may be difficult to understand for the inexperienced.
    // Please use the references to gain more information.
    static void InvMixColumns(state_t *state)
    {
        int i;
        uint8_t a, b, c, d;
        for (i = 0; i < 4; ++i)
        {
            a = (*state)[i][0];
            b = (*state)[i][1];
            c = (*state)[i][2];
            d = (*state)[i][3];

            (*state)[i][0] = Multiply(a, 0x0e) ^ Multiply(b, 0x0b) ^ Multiply(c, 0x0d) ^ Multiply(d, 0x09);
            (*state)[i][1] = Multiply(a, 0x09) ^ Multiply(b, 0x0e) ^ Multiply(c, 0x0b) ^ Multiply(d, 0x0d);
            (*state)[i][2] = Multiply(a, 0x0d) ^ Multiply(b, 0x09) ^ Multiply(c, 0x0e) ^ Multiply(d, 0x0b);
            (*state)[i][3] = Multiply(a, 0x0b) ^ Multiply(b, 0x0d) ^ Multiply(c, 0x09) ^ Multiply(d, 0x0e);
        }
    }

    // The SubBytes Function Substitutes the values in the
    // state matrix with values in an S-box.
    static void InvSubBytes(state_t *state)
    {
        uint8_t i, j;
        for (i = 0; i < 4; ++i)
        {
            for (j = 0; j < 4; ++j)
            {
                (*state)[j][i] = getSBoxInvert((*state)[j][i]);
            }
        }
    }

    static void InvShiftRows(state_t *state)
    {
        uint8_t temp;

        // Rotate first row 1 columns to right
        temp = (*state)[3][1];
        (*state)[3][1] = (*state)[2][1];
        (*state)[2][1] = (*state)[1][1];
        (*state)[1][1] = (*state)[0][1];
        (*state)[0][1] = temp;

        // Rotate second row 2 columns to right
        temp = (*state)[0][2];
        (*state)[0][2] = (*state)[2][2];
        (*state)[2][2] = temp;

        temp = (*state)[1][2];
        (*state)[1][2] = (*state)[3][2];
        (*state)[3][2] = temp;

        // Rotate third row 3 columns to right
        temp = (*state)[0][3];
        (*state)[0][3] = (*state)[1][3];
        (*state)[1][3] = (*state)[2][3];
        (*state)[2][3] = (*state)[3][3];
        (*state)[3][3] = temp;
    }
#endif // #if (defined(CBC) && CBC == 1) || (defined(ECB) && ECB == 1)

    // Cipher is the main function that encrypts the PlainText.
    static void Cipher(state_t *state, const uint8_t *RoundKey)
    {
        uint8_t round = 0;

        // Add the First round key to the state before starting the rounds.
        AddRoundKey(0, state, RoundKey);

        // There will be Nr rounds.
        // The first Nr-1 rounds are identical.
        // These Nr rounds are executed in the loop below.
        // Last one without MixColumns()
        for (round = 1;; ++round)
        {
            SubBytes(state);
            ShiftRows(state);
            if (round == Nr)
            {
                break;
            }
            MixColumns(state);
            AddRoundKey(round, state, RoundKey);
        }
        // Add round key to last round
        AddRoundKey(Nr, state, RoundKey);
    }

#if (defined(CBC) && CBC == 1) || (defined(ECB) && ECB == 1)
    static void InvCipher(state_t *state, const uint8_t *RoundKey)
    {
        uint8_t round = 0;

        // Add the First round key to the state before starting the rounds.
        AddRoundKey(Nr, state, RoundKey);

        // There will be Nr rounds.
        // The first Nr-1 rounds are identical.
        // These Nr rounds are executed in the loop below.
        // Last one without InvMixColumn()
        for (round = (Nr - 1);; --round)
        {
            InvShiftRows(state);
            InvSubBytes(state);
            AddRoundKey(round, state, RoundKey);
            if (round == 0)
            {
                break;
            }
            InvMixColumns(state);
        }
    }
#endif // #if (defined(CBC) && CBC == 1) || (defined(ECB) && ECB == 1)

/*****************************************************************************/
/* Public functions:                                                         */
/*****************************************************************************/
#if defined(ECB) && (ECB == 1)

    void AES_ECB_encrypt(const struct AES_ctx *ctx, uint8_t *buf)
    {
        // The next function call encrypts the PlainText with the Key using AES algorithm.
        Cipher((state_t *)buf, ctx->RoundKey);
    }

    void AES_ECB_decrypt(const struct AES_ctx *ctx, uint8_t *buf)
    {
        // The next function call decrypts the PlainText with the Key using AES algorithm.
        InvCipher((state_t *)buf, ctx->RoundKey);
    }

#endif // #if defined(ECB) && (ECB == 1)

#if defined(CBC) && (CBC == 1)

    static void XorWithIv(uint8_t *buf, const uint8_t *Iv)
    {
        uint8_t i;
        for (i = 0; i < AES_BLOCKLEN; ++i) // The block in AES is always 128bit no matter the key size
        {
            buf[i] ^= Iv[i];
        }
    }

    void AES_CBC_encrypt_buffer(struct AES_ctx *ctx, uint8_t *buf, size_t length)
    {
        size_t i;
        uint8_t *Iv = ctx->Iv;
        for (i = 0; i < length; i += AES_BLOCKLEN)
        {
            XorWithIv(buf, Iv);
            Cipher((state_t *)buf, ctx->RoundKey);
            Iv = buf;
            buf += AES_BLOCKLEN;
        }
        /* store Iv in ctx for next call */
        memcpy(ctx->Iv, Iv, AES_BLOCKLEN);
    }

    void AES_CBC_decrypt_buffer(struct AES_ctx *ctx, uint8_t *buf, size_t length)
    {
        size_t i;
        uint8_t storeNextIv[AES_BLOCKLEN];
        for (i = 0; i < length; i += AES_BLOCKLEN)
        {
            memcpy(storeNextIv, buf, AES_BLOCKLEN);
            InvCipher((state_t *)buf, ctx->RoundKey);
            XorWithIv(buf, ctx->Iv);
            memcpy(ctx->Iv, storeNextIv, AES_BLOCKLEN);
            buf += AES_BLOCKLEN;
        }
    }

#endif // #if defined(CBC) && (CBC == 1)

#if defined(CTR) && (CTR == 1)

    /* Symmetrical operation: same function for encrypting as for decrypting. Note any IV/nonce should never be reused with the same key */
    void AES_CTR_xcrypt_buffer(struct AES_ctx *ctx, uint8_t *buf, size_t length)
    {
        uint8_t buffer[AES_BLOCKLEN];

        size_t i;
        int bi;
        for (i = 0, bi = AES_BLOCKLEN; i < length; ++i, ++bi)
        {
            if (bi == AES_BLOCKLEN) /* we need to regen xor compliment in buffer */
            {

                memcpy(buffer, ctx->Iv, AES_BLOCKLEN);
                Cipher((state_t *)buffer, ctx->RoundKey);

                /* Increment Iv and handle overflow */
                for (bi = (AES_BLOCKLEN - 1); bi >= 0; --bi)
                {
                    /* inc will overflow */
                    if (ctx->Iv[bi] == 255)
                    {
                        ctx->Iv[bi] = 0;
                        continue;
                    }
                    ctx->Iv[bi] += 1;
                    break;
                }
                bi = 0;
            }

            buf[i] = (buf[i] ^ buffer[bi]);
        }
    }

    void SimpleAESEncode(BitArray &raw)
    {
        struct AES_ctx ctx;
        AES_init_ctx_iv(&ctx, AES_KEY, AES_IV);
        AES_CBC_encrypt_buffer(&ctx, (uint8_t *)(raw.operator char *()), raw.Size());
    }

    void SimpleAESDecode(BitArray &encrypted)
    {
        struct AES_ctx ctx;
        AES_init_ctx_iv(&ctx, AES_KEY, AES_IV);
        AES_CBC_decrypt_buffer(&ctx, (uint8_t *)(encrypted.operator char *()), encrypted.Size());
    }

#endif // #if defined(CTR) && (CTR == 1)
}